alda turned up all the way vs alda taken off - Page 3 - PeachParts Mercedes-Benz Forum

TurboSDL · #31 07-01-2009, 10:42 PM

and ill tell u this too, when i had my 87 sdl when i took the alda off i broke the shaft, right where the lock washer goes in and holds the spring on. it broke cuz when i took it off the intake manifold was in the way and i wasnt careful and broke the shaft. so if the spring isnt on there the shaft is always in the down position. if u try to drive it without the spring on there and the shaft in the down position the car will go nowhere. u can maybe on a straight road get the car to 10mph. i couldnt figure out what was causing the car to fall on its face i wasnt aware that the broken shaft was causing it because iv never seen what it looks like under the alda, it was broke when i removed it so i didnt kno what was goin on down there. and i took it to a mercedes dealership and they didnt even know what was wrong with it. so after a while i found out the shaft needed to stay in the up position and i put a piece of vacuum hose on there with jb weld holding it on to the piece of shaft that was left on there and ran the hose to between the fuel lines where it held pressure on it. this lasted about 3 hours then the jb came off and that failed. the piece of shaft was like broken below the surface so i couldnt just clamp it with vice grips or anything. the way i figured out that it was suposed to be in the up position is i put 90 degree needle nose in there and pulled the shaft up and when i started it , the shaft pulled down. so i put the angle needle nose back on there and vice grips on the needle nose and was able to go about a block and noticed that the problem was fixed... but i couldnt tell any performance increase because i never got it in a fixed position, the shaft was too far broken down so i had to put a used IP on there and left the alda alone after that... so i kno what goes on with that shaft and it has a great amt of strength pulling it down.

winmutt · #32 07-01-2009, 11:03 PM

Quote:

Originally Posted by OM616

The ADA and ALDA are the "Adjusting Units". They each are used for a specific application (altitude compensation and boost compensation), however, the linkage that the Adjusting Units move is the same, except possibly for the Preload Spring, because, as you pointed out, the ADA does not move much where the ALDA moves the shaft in to a grater degree. That being as it may, there may be a difference in the strength of the preload spring depending on whether an altitude change or boost increase is being compensated for.

I fairly certain the ALDA has two capsule where the ADA has one and that the ADA only moves in one direction from a starting position (sea level) where the ALDA has two capsules and moves in both directions.

OM616 · #33 07-02-2009, 01:58 PM

Quote:

Originally Posted by winmutt

I fairly certain the ALDA has two capsule where the ADA has one and that the ADA only moves in one direction from a starting position (sea level) where the ALDA has two capsules and moves in both directions.

I do not follow you thought process as to how this relates to the removal of the ALDA/ADA, and the inner workings that are affected in the governor. It would help if you could provide some foundation for your line of thought.

I have called out the "ALDA/ADA shaft" when speaking of it's, (the shaft’s), operation, because it's operation is the same regardless of whether it is on an NA or Turbo IP. The difference is the amount the shaft is moved.

For foundation, I have designed barometrically sensitive instruments. I continue to learn new aspects of that art on a daily basis, and I am open to any and all thoughts that contradict my current understanding.

The ALDA has two capsules (one on top of the other) to increase the travel output per given pressure change, because it is making large fueling adjustments to compensate for Boost. (for clarity, it should be noted that; because of the aneroid design, the capsules in the ALDA will react to changes in barometric pressure when the engine is not running)

The ADA has only one capsule, because it is making small-fine fuel adjustments to compensate for only barometric pressure changes.

Both the ALDA and the ADA use calibrated, aneroid type capsules, and as such, the capsules expand and contract according to their design, in reaction to changes in surrounding pressure. Both the ALDA and ADA are “Adjusting Units”. Adjusting each will result in the same thing internally in the governor.

The ADA is vented to the atmosphere and as such only sees barometric pressure changes.

The ALDA is vented to the intake manifold, where, when the engine is off, the capsules only see atmospheric, (barometric), pressure. When the engine is running in non-boost conditions, the ALDA capsules only see the pressure (or vacuum) in the intake manifold, regardless of the atmospheric (barometric) pressure, because the ALDA is sealed from the atmosphere. When the engine is running in boost conditions, the ALDA capsules see, and react to, the intake manifold pressure increase. Both the ADA and ALDA capsules react to what they think is barometric pressure. The design of the enclosure that each capsule is encapsulated in determines what that pressure really is.

dealwithit · #34 07-05-2009, 10:51 PM

so if i were to remove my alda and put some kind spacer there with a washer and thread the top of the shaft so a nut could be threaded on to keep it from droping would that do the same thing as mucking with the torque control nuts? mine has already been swapped into a truck, and i don't have any boost protection etc, and i do have an EGT guage too.

OM616 · #35 07-06-2009, 03:17 PM

Quote:

Originally Posted by dealwithit

i don't have any boost protection etc, and i do have an EGT guage too.

First, I definitely do not recommend changing anything in regards to the fueling curve with out an EGT gauge. Some may say that as long as it is not smoking black that you are safe, however, I turned a road race 616 and could see 1200* with very little, to no smoke to speak of.

Quote:

Originally Posted by dealwithit

so if i were to remove my alda and put some kind spacer there with a washer and thread the top of the shaft so a nut could be threaded on to keep it from droping would that do the same thing as mucking with the torque control nuts?

That is actually a complicated and tricky question that will require a good amount of discussion and research to determine a definitive answer to. The short answer is theoretically no and yes.

No in that the ALDA/ADA linkage position determines the Throttle to Rack travel ratio, where basically, in the up position the rack travel is increased, and in the down position the rack travel is decreased, for a for a given amount of throttle input.

The Torque Control controls the "power band" (for lack of a better description) portion of the fuel curve by balancing the Flyweight Load against the combined load of the Torque Control Spring, the Throttle Spring, and perhaps the Adjusting Unit Preload Spring. This is where the theoretical yes comes in.

If the ALDA/ADA Adjusting Unit Preload Spring is part of the calibrated forces that work against the flyweights, and in some cases each other, then the internal settings are adjusted taking the Adjusting Unit Preload Spring tension in to account.

Therefore, if a stronger Adjusting Unit Preload Spring was installed, or the shaft was to be mechanically restrained, provided no other adjustments were made, the internal calibration, (balance), would be out the window as some internal forces would be increased and some decreased. It is in this case that a theoretical yes may be appropriate. However more research needs to be done in order to definitively say what would actually be the result, (in regards of the fueling curve), of holding the ALDA/ADA shaft when the internals are calibrated for the shaft to move.

For example, if the Torque Control relies on the change of the Regulating Lever (rack) pivot point, as the result of the ALDA shaft lowering, to gain a mechanical advantage, and the shaft did not lower, then the Torque Control would be at a disadvantage, and the fuel curve would be altered.

This may prove to be like rcounts basically said, a quick and dirty way to change the fueling curve. That is if the all ALDA/ADA shafts move at high speed. My 616 Adjusting Unit Preload Spring is strong enough to hold the shaft up, however I have made internal adjustments.

I also am wondering how much torque is generated by the high velocity fuel flowing through the element helixes at the end of delivery, causing the elements to want to turn themselves. Just a thought I have that might account for the increased load on the ALDA/ADA bell crank at high engine speeds.

TurboSDL · #36 07-11-2009, 12:12 AM

so i used some mechanics wire and strung it tight around the lower part of the shaft, i got it inbetween the spring kinda and wrapped it around a few times, it is solid as a rock now, im about to travel 120 miles so ill see if its more responsive or whatever, it def smokes alot tho, i also ran the exhaust to exit the on the driver side behind the rear tire via turndown facing the side of the road; this way i can see how much smoke im making just by looking in the side view mirror.

TurboSDL · #37 07-12-2009, 11:37 PM

well after driving it about 300 miles it def seems to have a benifit on drivability. when cruising at hwy speeds you need to use much less throttle to hold a steady speed. when accelerating from a stop up to speed it def feels faster. i would suspect with the full load screw turned all the way up there would be more of a benifit. there is quite a bit of smoke tho once you press the pedal to the floor and i dunno if its just my exhaust exiting on the side but it sounds alot sweeter under acceleration, pretty equal to a cummins or powerstroke. on the hwy when you press the gas down all the way but without the trans downshifting u can feel more of a pull too it seems like but its hard to tell really how much. i was playing with boost levels alot too so its really hard to say what you can get out of this mod alone.

i would def try this if anyone has theyre alda off just to see what they think. the mechanics wire held real good, it did not let me push down the shaft at all and held for the trip. i would be curious to see what other people think.

TurboSDL · #38 07-16-2009, 08:29 PM

i explained it in the above post.... im gona leave it tied down because i like the way it drives with it in the up position all the time. and i like that if i step on it off the line i get alot of black smoke coming out of the exhaust. it also seems to use less pedal travel on the hwy to hold a steady speed. i cant really say what the gas mileage is like cuz i havnt got my odometer working but it seems to be the same.. i had a full tank and after 120 mile trip goin about 75-90 the whole way i had 1/4 tank which is normal for me, i dunno if i should be getting better but thats how its always been.

i think sombody with the IP maxed out should try this and see what they notice. id use mechanic wire tho because that shaft has a notch in it for the retainer clip that holds the spring in and it can easily crack in half right there and u will def cry if it does

tomnik · #39 07-17-2009, 12:55 AM

compared to a correct adjusted IP you just overfuel the low end.
The ALDA just cuts off the low end fuel.
There should be no difference in full load range.

Tom

rcounts · #40 07-17-2009, 01:22 AM

So if I am understanding correctly, you have secured the shaft of the ALDA in the highest UP position that you can by wrapping it tightly with light gauge wire?

If it is making smoke it is pushing more fuel than it can burn. At low RPMs (taking off from a dead stop) there isn't much you can do about that, but if it is still producing smoke at cruise speed, I think I'd install a boost controller and see if you can get the turbo pressure up enough to supply it some more air. That should convert that black smoke (wasted fuel) into power you can use...